Implementing SR-IOV for Red Hat Enterprise Linux on HP ProLiant Servers

Technical white paper | Implementing SR-IOV for Red Hat Enterprise Linux on HP ProLiant Servers
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Table 7. Red Hat Enterprise Linux host and guest operating systems
Host Operating System Guest Operating System
Red Hat Enterprise Linux 6.2 KVM (x86_64)
Red Hat Enterprise Linux 6.3 KVM (x86-64)
Red Hat Enterprise Linux 5.8 (x86 and x86_64)
Red Hat Enterprise Linux 5.9 (x86 and x86_64)
Red Hat Enterprise Linux 6.2 (x86 and x86_64)
Red Hat Enterprise Linux 6.3 (x86 and x86_64)
Windows Server 2008 SP1 (x86 and x86_64)
Windows Server 2008 SP2 (x86 and x86_64)
Enabling and configuring the SR-IOV feature
Use the following steps to enable and configure the SR-IOV feature
Enabling and configuring SR-IOV feature
1. Verify the HP ProLiant system is SR-IOV capable and running the correct ROM version.
2. Install a supported SR-IOV capable NIC in the system.
3. Enable the SR-IOV feature on the system using the ROM-Based Setup Utility (RBSU). Detailed instruction to enable the
SR-IOV feature can be found in the HP ROM-Based Utility User Guide to located at:
http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00191707/c00191707.pdf
4. Install one of the Linux Enterprise Server operating systems listed in the “Linux host and guest operating system for
enabling SR-IOV” section to enable SR-IOV.
5. Install the drivers for the NIC from the HP SPP website located at:
http://www.hp.com/go/spp
6. Create a virtual machine and install the Guest OS on a virtual machine. Instructions can be found in the Red Hat
Virtualization Guides.
7. Configure the NIC driver. Instructions can be found in the documentation provided for the NIC.
Special configuration steps on AMD HP ProLiant Servers running Red Hat Enterprise Linux 6.2 and later
AMD IOMMU does not support the software interrupt I/O remapping feature. For device assignment to a guest, enable the
kvm module option using the following command:
echo 1 > /sys/module/kvm/parameters/allow_unsafe_assigned_interrupts
To make this change persist across reboots, add the following to the file /etc/modprobe.d/kvm.conf (create this
file, if it does not already exist):
options kvm allow_unsafe_assigned_interrupts=1
Special configuration on Intel HP ProLiant Servers running Red Hat Enterprise Linux 6.2 and later
HP ProLiant Servers do not support hardware interrupt remapping. Please use the following command to override hardware
interrupt remapping on Intel platforms:
Boot kernel with intremap=no_x2apic_optout option
Limitations
If you create more than 45 virtual functions on Intel 82599 NIC, this results in a Kernel and Network package crash on Red
Hat Enterprise Linux 6.2. Due to Linux kernel networking table limitations, the Linux kernel can only support a maximum of
45 virtual functions even though the Intel 82599 NIC is capable of a maximum of 64 virtual functions.
After enabling SR-IOV and creating virtual functions on an Intel 82599 NIC, when more than 45 virtual functions are created,
the kernel and network package will crash due to the limit in kernel networking tables.
On any HP ProLiant Gen8 system with the SR-IOV feature enabled, and when the command modprobe ixgbe
max_vfs=63,63 is run to load ixgbe (Intel 82599 NIC driver), the following error message displays: